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This may be caused by various reasons, you may want to check and update (paths may differ for your deployment):
php.ini settings
File: /etc/php.ini
directives to update:
- post_max_size
- upload_max_filesize
ensure that you've restarted php-fpm after php.ini update:
systemctl restart php-fpm
nginx settings
In your nginx configuration you may want to locate or add client_max_body_size directive, ie in:
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